Right now recommended settings for 1080p 30fps and 720p 30fps are the same at 5000kbps (to be applicable for stream-copy). Would be nice if 1080p could have some extra bitrate. 1080p isn't even in recommended settings anymore.
1080p is unfortunately prohibitively expensive for us to serve at the moment. This will likely be the default in the future as bandwidth costs continue to fall.